The invention relates to a guide vane ring and a turbomachine in accordance with the present invention.
For establishing optimal operating conditions, turbomachines such as aircraft engines usually have, on the compressor side, at least one adjustable row of guide vanes having a plurality of guide vanes that can be pivoted around their vertical axis. The row of guide vanes forms a guide vane ring with an inner ring embracing a rotor segment. The inner ring serves for the inner stabilizing of the guide vanes. In known guide vane rings, a radial bearing of the guide vanes is produced via radial outer-lying adjusting journals of the guide vanes, these journals interacting with a corresponding adjusting mechanism on the stator side. This type of bearing is also named spoke-centered bearing. The radial inner stabilizing is usually produced via bearing journals that extend radially inward from a vane platform and are guided into bearing bushes of the inner ring. The bearing journals simultaneously represent a protection against disintegration in the case of strong axial movements of the inner ring relative to the guide vanes, for example, as a consequence of so-called pumping processes or a bird impact. Large forces are transferred to the guide vanes in the case of such axial movements, due to a very tight fit between bearing journal and bearing bush.
Guide vane rings that show such bearing journals are shown, for example, in U.S. Pat. No. 7,806,652 B2, U.S. Pat. No. 6,984,105 B2, US 2005/0031238 A1, US 2009/0208338 A1 and in U.S. Pat. No. 7,713,022 B2.
Guide vane rings without bearing journals are likewise known. These guide vane rings make possible a very flat construction of the inner ring, but tend to disintegrate in the case of a very large relative axial movement of the inner ring.